NASA’s Insight lander spent four years on the surface of Mars, uncovering secrets of the planet’s interior, but it eventually succumbed to the most martian of environmental threats: dust. Mars has periodic dust storms that can whip up into huge global events, lifting dust up into the air and then dumping it on everything in sight — including solar panels. After years of accumulation, eventually the dust was so thick that Insight’s solar panels could no longer generate enough power to keep it operational, and the mission officially came to an end in December 2022.
That wasn’t quite the end of the story for InSight, though, as it is still being used for science to this day, albeit indirectly. Recently, the Mars Reconnaissance Orbiter (MRO) caught a glimpse of InSight from orbit, capturing the lander’s dusty surroundings and showing how even more dust had built up on it.
This image was taken on October 23 of this year using MRO’s High-Resolution Imaging Science Experiment (HiRISE) camera. Researchers at NASA wanted to get one last image of InSight, to say farewell and to see how its environment had changed in the past two years.
“Even though we’re no longer hearing from InSight, it’s still teaching us about Mars,” said science team member Ingrid Daubar of Brown University. “By monitoring how much dust collects on the surface — and how much gets vacuumed away by wind and dust devils — we learn more about the wind, dust cycle, and other processes that shape the planet.”
Dust devils are like tiny tornadoes that occur frequently on Mars due to its thin atmosphere, and that sculpt the surface into dramatic shapes. Data from InSight showed that these were seasonal phenomena, being more common in summer and tailing off in the colder winter months. Tracks of dust devils are visible near to the InSight landing location, and researchers could match these tracks to data from the lander about wind speed and direction.
Another way dust shapes the landscape is by affecting craters on the Mars surface that are caused by meteoroid impacts. These craters are filled in over time with dust, so studying how fast they fade helps scientists understand how to date particularly craters.
“It feels a little bittersweet to look at InSight now,” said Daubar “It was a successful mission that produced lots of great science. Of course, it would have been nice if it kept going forever, but we knew that wouldn’t happen.”
